Overdosing on substances like heroin, club drugs, or even prescription pain medicines can kill you. But even if you don’t take a lethal dose, your health is at risk. Some harmful effects occur with prolonged use over time, but others occur after just one smoke, snort or shot. Your Cardiovascular System Consequences to your heart and blood vessels can be as mild as a rapid heartbeat or as serious as a heart attack. Methamphetamines, for instance, can cause high blood pressure that bursts blood vessels and causes a stroke. Injection drug use collapses veins and leads to bacterial infections of blood vessels and heart valves. The club drug ecstasy poses serious heart risks. It’s rapidly absorbed and also releases compounds that prevent the body from breaking it down. The longer it stays in your system, the greater your odds of developing irregular heartbeats or even heart failure. Anabolic steroid abuse can increase LDL, or “bad,” cholesterol, while lowering HDL, or “good,” cholesterol levels, contributing to heart attacks and strokes. Your Respiratory System The most obvious damage to your airways and lungs comes from drugs you breathe in, including marijuana, tobacco and inhalants. Snorting heroin or cocaine also breaks down your delicate nasal tissue. Over time, you can develop holes in your nasal septum—the tissue that separates the nasal passages. In addition, synthetic marijuana, or “spice,” often leads to trouble catching your breath. Inhalants—along with other depressants like heroin and painkillers—can actually slow your system to the point you stop breathing. Your Gastrointestinal System Cocaine, heroin, painkillers and spice can upset your stomach and cause nausea and vomiting, and cocaine often triggers abdominal pain. Any drug taken through the nose has the potential to lead to trouble swallowing. And heroin, no matter how it’s ingested, often causes constipation. Your Kidneys Cocaine and heroin can directly damage these organs so severely you need dialysis or a kidney transplant. And spice can have this effect almost immediately. Other drugs contribute to kidney failure in less direct ways. For instance, ecstasy use is often accompanied by vigorous physical activity. The combined effects of drug use and movement overheat your body, damaging your muscles and releasing toxic by-products into your bloodstream. When your kidneys attempt to filter them out, they wind up damaged and can fail completely. Your Liver Like your kidneys, your liver helps remove harmful waste products from your body. Drugs like inhalants overwork the liver to the point where it may malfunction or even fail. Injection drug use can increase your risk of catching viral hepatitis—which eventually leads to liver damage and failure. Steroid use can contribute to liver cancer. Your Nervous System Addiction isn’t the only dangerous brain condition linked to substance abuse. Drugs like cocaine, inhalants and methamphetamine can change the gray matter in your brain in ways that lead to paranoia, depression, hallucination, and aggressive behavior. A single trip on a hallucinogen like PCP or ketamine can cause immediate bouts of anxiety, memory loss, and impaired motor function. At high doses, you risk seizures, severe muscle contractions, and psychosis similar to schizophrenia. In the long term, you may experience trouble speaking, memory loss, suicidal thoughts, depression, or social withdrawal. Your Muscles and Bones Anabolic steroid use when you’re still growing can actually halt the development of your skeleton, leading you to be shorter than you should be. Inhalants, MDMA and PCP can cause muscle cramping and weakness. And inhalants can break down the myelin sheaths coating nerve cells, contributing to muscle spasms and tremors that could be permanent.